97819581389 has 2 divisors, whose sum is σ = 97819581390. Its totient is φ = 97819581388.

The previous prime is 97819581329. The next prime is 97819581479. The reversal of 97819581389 is 98318591879.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 97066518025 + 753063364 = 311555^2 + 27442^2 .

It is an emirp because it is prime and its reverse (98318591879) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 97819581389 - 2¹⁶ = 97819515853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (97819581329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 48909790694 + 48909790695.

It is an arithmetic number, because the mean of its divisors is an integer number (48909790695).

Almost surely, 2^97819581389 is an apocalyptic number.

It is an amenable number.

97819581389 is a deficient number, since it is larger than the sum of its proper divisors (1).

97819581389 is an equidigital number, since it uses as much as digits as its factorization.

97819581389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 39191040, while the sum is 68.

The spelling of 97819581389 in words is "ninety-seven billion, eight hundred nineteen million, five hundred eighty-one thousand, three hundred eighty-nine".